Arg-735 of the 100-kDa subunit a of the yeast V-ATPase is essential for proton translocation

  title={Arg-735 of the 100-kDa subunit a of the yeast V-ATPase is essential for proton translocation},
  author={Shoko Kawasaki-Nishi and Tsuyoshi Nishi and Michael Forgac},
  journal={Proceedings of the National Academy of Sciences of the United States of America},
  pages={12397 - 12402}
The vacuolar (H+)-ATPases (V-ATPases) are ATP-dependent proton pumps that acidify intracellular compartments and pump protons across specialized plasma membranes. Proton translocation occurs through the integral V0 domain, which contains five different subunits (a, d, c, c′, and c"). Proton transport is critically dependent on buried acidic residues present in three different proteolipid subunits (c, c′, and c"). Mutations in the 100-kDa subunit a have also influenced activity, but none of… 

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Subunit D (Vma8p) of the Yeast Vacuolar H+-ATPase Plays a Role in Coupling of Proton Transport and ATP Hydrolysis*

  • T. XuM. Forgac
  • Biology, Chemistry
    The Journal of Biological Chemistry
  • 2000
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A model of the a subunit containing nine transmembrane segments, with the amino terminus facing the cytoplasm and the carboxyl terminusfacing the lumen is proposed.

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